
#include "bsp.h"
#include "bsp_rs485.h"


#define TAG "RS485"


static void echo_send(const int port, const char* str, uint8_t length)
{
    if (uart_write_bytes(port, str, length) != length)
    {
        ESP_LOGE(TAG, "Send data critical failure.");
        // add your code to handle sending failure here
        abort();
    }
}

// An example of echo test with hardware flow control on UART
static void echo_task(void *arg)
{
    // Allocate buffers for UART
    uint8_t* data = (uint8_t*) malloc(BUF_SIZE);

    while(1) 
    {
        //Read data from UART
        int len = uart_read_bytes(ECHO_UART_PORT, data, BUF_SIZE, PACKET_READ_TICS);

        //Write data back to UART
        if (len > 0) 
        {
            echo_send(ECHO_UART_PORT, "\r\n", 2);
            char prefix[] = "RS485 Received: [";
            echo_send(ECHO_UART_PORT, prefix, (sizeof(prefix) - 1));
            ESP_LOGI(TAG, "Received %u bytes:", len);
            printf("[ ");
            for (int i = 0; i < len; i++)
            {
                printf("0x%.2X ", (uint8_t)data[i]);
                echo_send(ECHO_UART_PORT, (const char*)&data[i], 1);
                // Add a Newline character if you get a return charater from paste (Paste tests multibyte receipt/buffer)
                if (data[i] == '\r')
                {
                    echo_send(ECHO_UART_PORT, "\n", 1);
                }
            }
            printf("] \n");
            echo_send(ECHO_UART_PORT, "]\r\n", 3);
        } else
        {
            // Echo a "." to show we are alive while we wait for input
            echo_send(ECHO_UART_PORT, ".", 1);
            ESP_ERROR_CHECK(uart_wait_tx_done(ECHO_UART_PORT, 10));
        }
    }
    vTaskDelete(NULL);

}




void bsp_rs485_init(void)
{
    const int uart_num = ECHO_UART_PORT;

    uart_config_t uart_config = {
        .baud_rate = BAUD_RATE,
        .data_bits = UART_DATA_8_BITS,
        .parity = UART_PARITY_DISABLE,
        .stop_bits = UART_STOP_BITS_1,
        .flow_ctrl = UART_HW_FLOWCTRL_DISABLE,
        .rx_flow_ctrl_thresh = 122,
        .source_clk = UART_SCLK_APB,
    };

    // Set UART log level
    esp_log_level_set(TAG, ESP_LOG_INFO);

    ESP_LOGI(TAG, "Start RS485 application test and configure UART.");

    // Install UART driver (we don't need an event queue here)
    // In this example we don't even use a buffer for sending data.
    ESP_ERROR_CHECK(uart_driver_install(uart_num, BUF_SIZE * 2, 0, 0, NULL, 0));

    // Configure UART parameters
    ESP_ERROR_CHECK(uart_param_config(uart_num, &uart_config));

    ESP_LOGI(TAG, "UART set pins, mode and install driver.");

    // Set UART pins as per KConfig settings
    ESP_ERROR_CHECK(uart_set_pin(uart_num, ECHO_TEST_TXD, ECHO_TEST_RXD, ECHO_TEST_RTS, ECHO_TEST_CTS));

    // Set RS485 half duplex mode
    ESP_ERROR_CHECK(uart_set_mode(uart_num, UART_MODE_RS485_HALF_DUPLEX));

    // Set read timeout of UART TOUT feature
    ESP_ERROR_CHECK(uart_set_rx_timeout(uart_num, ECHO_READ_TOUT));

    ESP_LOGI(TAG, "UART start recieve loop.\r\n");
    echo_send(uart_num, "Start RS485 UART test.\r\n", 24);



    //A uart read/write example without event queue;
    xTaskCreate(echo_task, "uart_echo_task", ECHO_TASK_STACK_SIZE, NULL, ECHO_TASK_PRIO, NULL);

}
